数字电视图象压缩编码

本文对各类电视图象压缩编码方法的原理、特点和进展作了较系统的综述。包括变换编码、预测编码、矢量量化编码、运动补偿编码和电视图象信号的亚奈奎斯特取样。对图象信号的特点、视频信号的数字化和电视图象压缩编码在综合业务数字网中的重要作用也作了简述。     

用FPGA实现图象格式的转换

1　引言　　在多媒体通信 (如可视电话、会议电视等 )图象传输业务中 ,如能在公用电话网上传送视频信号 ,因为公用电话网费用低、普及程度高 ,这些业务的成本会极大降低 .但是 ,现行电话网传输数据的位率在 33.6ｋｂｉｔ/ｓ以下 ,针对这种情况 ,ＩＴＵ Ｔ提出了一种极低码率视频编码标准Ｈ .2 6 3建议 .Ｈ .2 6 3标准要求所有编码器能以Ｓｕｂ ＱＣＩＦ(以下简称ＳＱＣＩＦ)或ＱＣＩＦ作为标准图象输入格式 .如图 1所示 ,即需将摄像头进入的模拟复合视频信号经解码和Ａ/Ｄ变换为ＣＣＩＲ 6 0 1规定的分量编码 4∶2∶2标准的亮度和色度信号之…     

会议电视图像编解码器中的视频格式转换

提出了一种实用的存取转换法，可用于会议电视系统中将扫描格式的数字视频信号转换为符合ＩＴＵ－ＴＨ．２６１标准的ＣＩＦ格式的视频信号。讨论了这种方法的设计要点和实现机理     

计算机辅助工艺设计系统（CAPP）

介绍ＣＡＰＰ系统及其组成，并重点介绍零件编码的实现和码位的定义，讨论ＣＡＰＰ的构成及其存在问题．通过对工厂的ＣＡＰＰ开发研究，在比较了ＪＣＢＭ．ＪＬＢ－ＩＯＰＩＴＺ．ＫＫ－３等编码基础上，据我国现行工艺的水平及计算机技术的发展，提出了在ＫＫ－３基础上的扩充编码，并简单介绍ＣＡＰＰ实现的流程及方法，提出一种综合的ＣＡＰＰ设计方法．     

CCITTG.722音频编码系统及其编,解码器的设计与实现

ＣＣＩＴＴＧ．７２２建议书描述的是一种５０￣７０００Ｈｚ音频信号的压缩编码系统，码率为６４ｋｂｉｔ／ｓ。该系统采用了子带自适应差分脉冲编码技术（ＳＢ－ＡＤＰＣＭ），具有ＦＭ广播的音质。本文简介了Ｇ．７２２压缩编码系统，介绍了运用ＴＭＳ３２０Ｃ２５定点高速数字，处理器实时实现编、解码算法的方法，分析了编、解码器的工程实现中要解决的主要问题。     

一种自适应图象压缩编码算法

提出了一种自适应图象压缩编码算法（ＡＣＣ）,该算法将绝对矩方块截断编码算法（ＡＭＢＴＣ）、内插法和四叉树技术有机结合起来,根据图象的局部特性调节编码算法．仿真结果表明ＡＣＣ算法与文献［５］中自适应算法相比,在相同的压缩倍数下,能得到更好的编码性能．     

用于PACS系统的医学图象量化编码的算法

图象压缩是PACS系统的重要研究部分。作者研究了二维图象小波分解后系数的统计分布与拉普斯分布有很好的一致性；同时，由于不同幅度的小波系数在图象重构中权重的不同，在系数压缩编码时对不同权重的系数采用不同的压缩精度。由此，作者提出了一种适用于PACS系统的图象量化编码算法，该算法以各小波子带图象小波系数的重要统计特征-样本标准差为量化阈值选择依据，精确编码图象重构中权重较大的系数，还利用了人眼的频率视觉特性。实验表明，本算法具有计算简单、不同编码精度时被量化系数可预见的特点，同时在保证图象质量的基础上可获得较高压缩比。     

微光图象时空噪声处理理论与技术研究

该文以研制出的微光ＣＣＤ电视系统为实验研究对象，在系统研究了微光图象特征及其噪声特性的基础上，建立了同时考虑时间域噪声与空间域噪声的微光图象噪声理论模型。研制了微光图象处理实验系统，在理论模型的指导下，提出并发展了时间域帧间比较去噪法和空间自适应众值滤波法这２种新型的微光图象噪声处理技术，并对微光图象进行了时空域组合噪声抑制处理。文末对处理前后图象进行了测试与分析评价。     

H.263+部分可选模式的研究

在阐述了ＩＴＵ－ＴＨ．２６３“低码率图像通信”国际标准及其编码可选模式的基础上,详细讨论了Ｈ．２６３Ｖｅｒｓｉｏｎ２（Ｈ．２６３＋）及其３种可选模式的编码机理,最后,通过计算机对比证实了Ｈ．２６３＋可提高压缩性能,并讨论了３种可选模式的复杂度,内存要求等。     

关于高校内部管理的四个标准

关于高校内部管理的四个标准ＯＮＦＯＵＲＣＲＩＴＥＲＩＡＯＦＴＨＥＩＮＴＥＲＩＯＲＭＡＮＡＧＥＭＥＮＴＯＦＴＨＥＵＮＩＶＥＲＳＩＴＩＥＳＡＮＤＣＯＬＬＥＧＥＳＣｈｅｎＺｈａｎｇｍｉｎｇ（ＺｈｅｊｉａｎｇＦｉｓｈｅｒｉｅｓＣｏｌｌｅｇｅ，Ｚｈｏｕｓｈａｎ...     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.